1. Field of the Invention
This invention relates generally to control apparatus for motor vehicles and, more particularly, to improved supercharger control apparatus for use in conjunction with an internal combustion engine of a motor vehicle.
2. Description of the Prior Art
A supercharger can be driven by the output torque of an internal combustion engine to supercharge the air flow being routed into the intake manifold of the engine. The operation of such a supercharger is effective in increasing the output torque of the engine thereby satisfying acceleration requirements when demanded; however, the operation also causes increased fuel consumption under normal driving conditions of the motor vehicle.
One conventional supercharger system for motor vehicles utilizes a control device which controls the activation and deactivation of the supercharger in accordance with demand signals for vehicle acceleration. The demand signals are a function of the relation between an acceleration signal (such as the amount of throttle valve opening) and the rotational speed of the engine. This two-staged, on-off controlling of the supercharger has a major drawback, however, since supercharged conditions of the engine cannot be appropriately tailored to the various particular driving states of the vehicle. Additionally, the control system has hunting problems. Furthermore, the use of such systems has an adverse effect on fuel consumption efficiency.
An object of the present invention is, therefore, to provide improved supercharger control apparatus which overcomes the aforementioned disadvantages of the conventional supercharger control system.